Two-cycle combustion-engine.



G. FORNACA.

TWO-CYCLE COMBUSTION ENGINE.

APPLICATION FILED mAR.1z.|si4.

1,176,951 I Patented Mar. 28, 1916.

Ba g] 2 SHEETSSHEET 1- 5 vw Mioz 7W Magnum/1 0g w G;FORNACA. v TWO-CHILE COMBUSTION ENGINE.

I APPhIATION FILED MAR. 17. 1914. 1,176,951

Patented Marf28, 1916 2 SHEETS- SHEET 2.

Fig.3.

wi/wveweo GUI'IDO FOBNA -CA, F TURIN, ITALY.

Two-crow COMBUSTION-ENGINE.

To all whom it concern: I

- -Turi n,-in the Province of'Piedmont, Italy, have inventedcertain: new and useful Im-.

Be it known that I, GUIDo FoeNnoA, a subject ofthe King of Italy, residing at .p'rovements in 'Two Cy'cle Combustion-Engines, of which the following and exact specification.

This invention'relates to two-cycle combustion engines,and hasparticular reference to enginesof-the'type wherein the burned gases are forced out through the exhaust port by a blast of compressed air, a portion of which air is retained in the cylinder and mixed with the next fuel charge.

The object of the invention is to' provide'a controlling means for the blast by which the pressure, and thereby renderedcapable of blast will notbe admitted to the cylinder until after the working piston has opened the exhaust port, and permitting the admission of air-even after the working piston closes the exhaust port on the return stroke. The further object of the invention is to locate the blast controlling mechanism at the outer or lower end of the cylinder, so that it will be protected from excessive heat and beingmoresimply constructed and operated. The invention is-especially applicable to the Diesel type "of two cycle engine, wherein the fuel is i jected into-air compressed in the cylinder, forming a charge which is ignited by the heat of compression. In the' embodiment of they invention" shown herein, the outerv end of the cylinder is provided with an exhaust port or ports on one side which areopened j-ustbefore the piston reaches the outer end of its working stroke, and opposite to the exhaust ports areplaced blast inlet ports, which are uncovered by'the piston 'be-:

fore it uncovers the exhaust-yp'orts, and cov} ered by the piston after it covers the exhaust ports. For controlling the blast, an external mechanically driven valve is provided, which opened and partially "exhausted the gases, and continues the admission. of air even after the exhaust ports have closed, thereby scour-- ing an economy by permitting the burned gases to naturally exhaust down to atmospheric pressure and also enabling a suflicient duration of blast inlet to fully charge the cylinder with fresh air.

In the accompanying drawings, Figure-1 isa vertical section of a cylinder'embody- Specification of Letters Patent. I

ing

is a full, clear,

' the inner blast port arrow in Fig. 4..

I wardly and the is that the become equal to that of the scavenging reservoir, which in effect corresponds to an increase in the volume of air in coeperation with the stationary ports only, admits the blast after theexha'ust ports have.

Patented Mar. 28, 1916.

Application filed March '17, 1914. Serial No. 825,222.

the invention; Fig. is a horiz ontalsect1on,-and F igs. 3, 4 and 5 are diagrams showing a preferred timing of the various parts.

1 vrepresents a cylinder having a working piston 2, exhaust ports 3, blast inlet ports 4, a blast supply pipe 5 and a rotary blast controlling valve 6. The fuel may be admitted at the top "of the cylinder through suitable valves disposed in the hole 7. The piston 2 maybe provided with a curved head as 8, or other suitable formation to properly direct the air blast so as to fully fill the entire cylinderand expel the burned gases through ports 8.

the piston after the exhaust of burned gases throughports 3 has commenced, but the air blast is still cut off by valve 6, even though ports 4 were uncovered by the piston 2 before it uncovered exhaust ports 3. Up to this time, the gases in the cylinder exhaust practically down to atmospherlc pressure without any external air pressure. In Fig. 4, the piston 2 is almost at its outer dead center, with maximum opening of the exhaust ports 3, and the valve 6 opening to permit the air to enter through ports 4. It will be observed that the air ports flare toward the cylinder head and the first vair admitted strikes the upper corner of the wardly, as shown by the arrow in Fig. 4,

piston and is deflected up-.

thereby causing theexhaust gases to pass out through port 3 as shown by the exhaust In, Fig. '5, the piston 2 has moved upon the return stroke and closes the exhaust ports 3, but air is still being admitted to the cylinder through the valve 6 ports 4. The advantage of this pressure in the cylinder can which will be permits of. burning a greater quantity of fuel, and therefore increases the efficiency of the engine.

The distributing valve 6 in combination with the wide blast ports 4 is thus located so asto be away-from the excessive heat at the head of the cylinder, and can be easily driven and lubricated,,because'it is only subject to the airpressure and not to hot gases. -.It may be driven from the main enginexshaft atthe same speed, and suitably timed, and

70 5' Referring to Figs. 3, 4 and 5, Fig. 3 shows I a an I: an

of course with a multiple cylinder engine these distributing valves 6 will control each cylinder in proper sequence.

The invention is readily applicable to reversing engines, to accomplish which it is simply necessary to alter the relative position ofthe distributing valve 6 to the engine shaft, as byturning the shaft of the valve 6 through a certain angle while the main shaft is stationary. Means for doing this, such as lost motion connections or spaced driving lugs, are well known and are unnecessary to a full understanding of this invention.

Having thus described my invention, ll declare that what I claim as new and desire to secure by Letters Patent, is

1. The combination with a cylinder having blast and exhaust ports, and a piston controlling said ports, of a'valve controlling the entire blast, opening after said piston has uncovered both of said ports, and'cutting off the blast after the piston has closed said exhaust.

2. The combination witha cylinder having a blast inlet port and ,an exhaust port adjacentits outer end, and a piston, of

blast controlling means for admitting the initial blast a predetermined time after saidpiston Opens said exhaust port, and cutting ofi said blast-a predetermined time after the piston closes the exhaust port.

3. The-combination with a cylinder having blast and exhaust ports at its lower end,

manner of a mechanically driven valve for delaying the entire blast a predetermined time after the exhaust is opened by the piston and conexhaust port has been opened and cooperating with said flared port to direct the blast upwardly toward the head of the cylinder. i

5. In a two-cycle engine, a cylinder having an exhaust port and an elongated blast port; arotary valve controlling said elongated blast port and rotating therein in such a direction as to direct the blast first on the head of the piston, then upwardly toward the cylinder head as the piston travels on its compression stroke. I

In testimony whereof I afiix my signature, in presence of two witnesses.

GUIDO FORNACA.

Witnesses: 

